The present application relates generally to measuring and/or correcting aberrations of an eye. More particularly, the present invention relates to systems and methods for orienting sensors of a wavefront system used to measure aberrations of an eye.
Laser eye surgical procedures often employ some sort of system that measures optical characteristics of a patient's eye. An example of such an eye measurement system is the VISX WaveScan® System, which uses a Hartmann-Shack wavefront sensor. A Hartman-Shack wavefront sensor can quantify aberrations present in an optical system such as an eye. Examples of aberrations include first and second-order aberrations such as prism, sphere and cylinder which are readily corrected with spectacles. Additional aberrations, such as coma and spherical aberration and other third through sixth-order aberrations can also be measured and quantified. A wavefront measurement of an eye creates a high order aberration map that permits assessment of aberrations throughout an optical path of an eye. Contributions of both internal optical tissue surfaces and external optical tissue surfaces to an eye's aberrations are measured. Thereafter, wavefront aberration information can be saved and input into a laser system to compute a custom ablation pattern to correct aberrations present in a patient's eye.
Like many aberration measurement systems, a WaveScan® System also includes a camera (“pupil camera”) that takes images of an eye while wavefront measurements are taken with a Hartmann-Shack wavefront sensor. Images of the eye taken with a pupil camera can also be used to track a spatial position of the eye so as to properly align an ablative laser with the eye during a corneal ablation treatment.
Because laser treatment of an eye can be based on an image taken with a pupil camera and a measurement taken with a wavefront sensor, it is important that wavefront data are properly oriented with the image taken with the pupil camera. If the pupil camera and wavefront sensor are not properly oriented when a wavefront measurement is obtained, a subsequent laser assisted corneal ablation may not be properly oriented with the patient's eye.
Manufacture and assembly of systems used to measure an eye can be expensive and time consuming. During assembly of such systems, an incorrect orientation of system components can lead to problems if not detected. Also, detecting an incorrect orientation of a system component can be time consuming. Consequently, systems and methods providing an improved orientation among optical sensors are desirable.